The present invention relates to a window molding applied to a front window of an automotive vehicle, a method and an apparatus for producing the same.
Various window moldings and methods of producing the same have been proposed and are in practical use. Japanese Patent Provisional Publications Nos. 8-25385 and 7-285329 respectively disclose typical window moldings and methods of producing the same. The window molding disclosed in the Japanese Patent Provisional Publication No. 8-25385 is formed such that a side molding 304 having a rainwater guide groove 303 is integrally molded with an upper molding 306 installed at an upper portion of a front window 307, as shown in FIGS. 26 and 27. The rainwater guide groove 303 is defined by a head portion 309 for covering a clearance between the front window 307 and a vehicle body 312, a glass limiting lip 311 for sealingly pressing the front window 307 and a strut portion 310 extending from a leg portion 308 inserted between the clearance. The head portion 309 and the glass limiting lip 311 in the upper molding 306 are overlapped with each other and united so as not to define the rainwater guide groove 303. The length of the strut portion 310 is gradually increased from a connecting portion between the upper and side moldings 306 and 304 to the other end of the side molding 304 so as to increase the volume of the rainwater guide groove 303.
On the other hand, the window molding 370 of the Japanese Patent Provisional Publications No. 7-285329 is arranged such that a head portion 374 and a glass limiting lip 378 are overlapped and connected to form a closed hollow 380 therebetween. The hollow 380 at an upper molding 371 is thin and constant in cross section, and the hollow 380 at the side molding 372 is gradually increased such that a surface 374a receiving rainwater is gradually increased in its height H from H.sub.1 to H.sub.2 as shown in FIGS. 28 and 29. This window molding 370 is molded by an apparatus including an upper fixed die head 353 for extruding an upper part of the window molding 370 and a lower rotatable die head 354 for extruding a lower part of the window molding 370 as shown in FIG. 30.
However, the former window molding has a limitation that a projecting amount of the head portion 309 from an outboard surface of the vehicle body 312 becomes too large if a volume of the rainwater guide groove 303 is sufficiently ensured. On the other hand, the latter window molding 370 is molded such that a leg portion 373 is gradually twisted according to the change of the height of the head portion 374 with respect to the upper surface of the head portion 374. Therefore, the leg portion 373 of the side molding 372 is twisted with respect to the leg portion 373 of the upper molding 371. This twist applies twisting force to the leg portion 373 of the side molding 372 when corrected by a sizing jig and may degrade the positional and shaped accuracy of the leg portion 373 of the side molding 372.